A Theoretical Study of Thermolysis of 2, 4, 6-triazido-1, 3, 5-trinitrobenzene

The thermolysis mechanism of 2, 4, 6-triazido-1, 3, 5-trinitrobenzene（TATNB）has been studied with PM3-MO method and by principles of thermodynamies, statistical thermodyamics and transition state theory of reaction rate. The fully optimized geometries and electronic structures of reactant, thansition state, and product, and the thermodynamical and kinetic palametere for every elementary reacton of TATNB pyrolysis have been obtained. The calculated results show:（1） the activation energy of N-N₂ bond cleavage or C-NO₂ bond homlysis for TATNB pyrolysis is much larger than that of cyclization, so TATNB decomposes through the "furoxan mechanism "; （2） the first step that TATNB decomposes to 4, 6-diazido 3, 5-dinitrobenzofuroxan is the controlling step. In addition, the influence of temperature on the TATNB thermolysis has been discussed.